KR20110139209A - Compression casing for a fuel cell stack and a method for manufacturing a compression casing for a fuel cell stack - Google Patents

Abstract

The fuel cell or electrolytic cell stack has a force distribution member that is flat on one side and convex on one side, which applies at least to the top and bottom of the stack and in one embodiment also to the two sides. A compression mat and an additional fixed rigid collar surround the stack and the force distribution member, whereby the stack is subjected to compressive force at least on the top and bottom and potentially also on two sides. The assembly has an essentially oval or circular shape, is substantially airtight in the axial direction, and has a gastight end plate so that a rigid gas inlet and outlet manifold can be formed.

Description

Compression casing for fuel cell stack and manufacturing method of compression casing for fuel cell stack {COMPRESSION CASING FOR A FUEL CELL STACK AND A METHOD FOR MANUFACTURING A COMPRESSION CASING FOR A FUEL CELL STACK}

FIELD OF THE INVENTION The present invention relates to the compression of cell stacks, and more particularly to compression casings for fuel cell stacks or electrolytic cell stacks, and to the production of such compression casings, in particular solid oxide fuel cell (SOFC) stacks or solid oxide electrolytic cells (SOEC). The manufacture of compression casings in stacks.

The invention will now be described with reference to SOFC stacks. However, the compression casing according to the invention can also be used for other types of fuel cells, such as polymer electrolyte fuel cells (PEM) or direct methanol fuel cells (DMFC). The present invention can also be used in electrolytic cells, such as solid oxide electrolytic cells, and in such cell stacks.

The electrochemical reactions and functions of fuel cells or electrolytic cells are not the essence of the present invention and therefore will not be described in detail under the knowledge that those skilled in the art are familiar with.

Several battery units are assembled to form a stack to increase the voltage generated by the SOFC, which are connected together by interconnects. These layers of the stack are sealed together in a gas tight manner with a heat resistant seal such as glass along a portion or the entire edge of the edge. The interconnect acts as a gas barrier to separate the anode (fuel) side and the cathode (air / oxygen) side of adjacent cell units, while at the same time they are between adjacent cells, i.e. the anode and reduction process of a cell with extra electrons. Current can be induced between the cathodes of neighboring cells for which electrons are needed. Current induction between the interconnect and its neighboring electrodes is made possible through a plurality of contact points distributed throughout the interconnect area. The contact points can be formed as protrusions on both sides of the interconnect. The efficiency of the fuel cell stack depends on the contact goodness at each of these contact points, so it is important that a suitable compressive force be applied to the fuel cell stack. This compressive force should be large enough to ensure electrical contact and evenly distributed throughout the fuel cell area, but not so large as to damage the electrolyte, electrodes, interconnects, or impede the flow of gas over the fuel cell. Compression of the fuel cell is also important for sealing between stack layers to keep the stack airtight.

A solution to this problem has been proposed in WO 2008089977, which describes how the fuel cell stack has a thermally insulated end block having a rectangular planar side facing the stack and an opposite side of the convex shape. As the spring tightens the flexible sheet against the convexly shaped face of the end block, the force of the spring is uniformly distributed throughout the stack end region.

DE 10250345 provides a housing surrounding the SOFC, where a compression mat between the stack and the housing provides compression to the cell radially and axially.

WO 2006012844 describes the manner in which the stack is tensioned through the spring, which for example exerts a force on the hemispherical pressure distribution element against the thermally insulated element and then presses further onto the stack.

In WO 2008003286 the stack is compressed by a thermally insulated element, which is pressed against the stack by an elastic sleeve. The sleeve can be made of silicone or natural raw rubber, for example.

Another stack compression principle is presented in DE 19645111.

Although there are known known solutions to the compression problem of fuel cell stacks, they all have some inherent problems:

-The more components included in the compression system, the higher the production cost and the higher the material cost. In addition, as the number of components increases, the risk of dysfunction generally increases.

The use of metal springs to compress the stack increases the cost, especially since metal springs tend to degrade when exposed to heat, the spring characteristics and thus the compressive force change over time.

A solution using raw rubber as a pressure generating device may, for example, enable mechanical and process connection with the peripheral system and may require an additional stationary housing on the metal to protect the compression assembly.

Solutions that do not use convex force distribution members present a risk of pressure unevenness throughout the stack area and hence insufficient electrical contact and risk of disturbing the stacking of fuel cell stack components.

For crimping solutions that are not hermetic, manifolds are required as extra components for gas distribution, which is expensive, requires precise techniques for attachment, and in particular several stacks connected in series and / or in parallel If necessary, it complicates the fuel cell system.

-Solutions that do not use a tight, strong external surface are susceptible to damage during handling, supply and operation.

It is an object of the present invention to solve the problems mentioned by providing a new compression casing assembly for one or more cell stacks.

More specifically, it is an object of the present invention to provide a compression casing assembly that eliminates the need for a metal spring to compress the cell stack.

Another object of the present invention is to provide a compression casing assembly that forms a pressure resistant vessel that can withstand the pressure present in, for example, a turbine system.

Another object of the present invention is to provide a compression casing assembly capable of withstanding high ambient temperatures.

It is another object of the present invention to provide a compression casing assembly that provides a substantially airtight enclosure on at least four sides of the cell stack.

Another object of the present invention is to provide a compression casing that provides substantially airtight separation on two opposite sides of the cell stack, in one embodiment this is the separation of the oxidizing gas inlet side and the oxidizing gas outlet side of the cell stack.

It is another object of the present invention to provide a compression casing assembly that provides a uniform pressure distribution or a well defined pressure distribution throughout the area of a fuel cell or electrolytic cell in a cell stack.

Another object of the present invention is to provide a compression casing assembly that thermally insulates a cell stack.

Another object of the present invention is to provide a compression casing assembly that provides vibration damping and protection of the cell stack.

Another object of the present invention is to provide a compression casing assembly composed of a few stable components.

It is another object of the present invention to provide a rigid and durable weldable compression casing assembly in which a compression system and manifold are integrated into the assembly to protect the fuel cell and provide easy handling and mounting.

It is another object of the present invention to provide a compression casing assembly capable of easily intimate, durable series and parallel cathode flow connection of two or more stacks.

It is another object of the present invention to provide a compression casing assembly inherently capable of a simple connection for the extra injection of process gas or fluid.

These and other objects are achieved by the present invention described below.

Thus, compression casing assemblies are provided, which are particularly suitable for stacks of solid oxide fuel cells or solid oxide electrolytic cells as well as potentially other known cell types already mentioned. The essence of the present invention is a compression casing assembly, which is not an electrochemical reaction occurring in a cell, so that the fuel cell stack or electrolytic cell stack will be considered as a black box. Accordingly, in the case of fuel cells, the black box generates electricity and heat when oxidizing gas and fuel gas are supplied, or in the case of electrolytic cells, the black box generates oxidizing gas and fuel gas when electric power is supplied. However, depending on the electrical load, the black box produces or consumes heat. The function and internal components of the fuel cell stack or the electrolytic cell stack are considered to be known in the art and are not subject to the present invention.

The fuel cell or electrolytic cell stack may have a variety of physical forms, which do not limit the invention, but for simplicity of the invention the following description and examples are box-shaped, i.e. six rectangular faces and eight A cell stack with twelve edge sides arranged in substantially perpendicular connection to three corners will be selected as a starting point. The cell stack is then specified as having a top, bottom, and multiple sides. Therefore, the precondition of the present invention is that the compressive force is required in such a manner that the upper surface is pressed toward the lower surface at least on the upper surface and the lower surface. Optionally, compressive forces on each other on the two opposite sides of the stack are needed, and in some cases compressive forces on each other on the other two opposite sides.

In order to distribute the compressive force and optionally also provide thermal insulation, a rigid force distribution member having a plane on one side and a convex shape on one side is disposed with respect to the top side of the stack, and one with respect to the bottom side of the stack. Optionally, a force distribution member may also be applied to two or more of the sides. A flexible compressive force mat is applied around the stack and the assembly of the force distribution member, which is characterized by being compressible when a compressive force is applied. The compressive distance is related to the compressive force magnitude, so that the necessary compressive force to be applied to the force distribution member and even to the stack can be achieved by compressing the mat by a corresponding distance. Compression of the mat is maintained by applying a rigid collar fixed around the stack and the force distribution member and the assembly of the compression force mat. In this regard, "stiffness" means that it is rigid with respect to traction, so that the thin metal sheet is sufficiently rigid with respect to traction so that the necessary fixation can be applied. The fixed collar is tightened around the compression mat until the required compression distance or associated compression force is reached, after which the collar is fixed in this taut position. The fixed collar may comprise one or more compartments, all of which are fixed.

1. A compression casing assembly for at least one cell stack made of a plurality of fuel cells or electrolytic cells, wherein at least one cell stack

Top

-Bottom side

-Multiple aspects

Fuel gas inlet and outlet adapted to communicate with fuel gas inlet and outlet manifolds;

Oxidant gas inlet and outlet adapted to communicate with oxidant gas inlet and outlet manifolds;

Including,

The compression casing assembly comprises at least one rigid force distribution member, at least one flexible compressive force mat and at least one fixed rigid collar comprising an inner surface, an outer surface and first and second side edges,

At least one force distribution member

An upper portion having a first planar surface facing the top of the cell stack and a second convexly shaped second surface opposite the first planar surface facing in the direction towards the inner surface of the fixed collar;

A lower portion having a first planar surface facing the bottom of the cell stack and a second surface of essentially convex shape opposite the first planar surface facing in the direction towards the inner surface of the fixed collar;

Including;

The fixed rigid collar surrounds at least one cell stack, at least one force distribution member and at least one flexible compressive force mat at least on the top, the bottom and two of the sides,

The fixed rigid collar is pre-tensioned so that a compressive force perpendicular to the surrounding fixed rigid collar is essentially perpendicular to the top, the bottom and the two sides by at least one flexible compressive force mat and at least one force distribution member. Is delivered to at least one cell stack in the

Thus, a compression is characterized in that the basically convexly shaped second surface of the upper and lower portions of the at least one force distribution member provides a uniformly distributed surface pressure on at least the top and bottom surfaces of the at least one cell stack. Casing assembly.

2. The feature of feature 1 above, wherein the at least one force distribution member and the at least one compressive force mat are secured to the top, bottom and two sides of the at least one cell stack and the surroundings at least in part of the axial range of the collar. A compression casing assembly, characterized in that a substantially airtight seal is formed between the inner surfaces of the rigid collar.

3. The feature of item 2 above, wherein a first end plate is secured to the collar near the first side edge and a second end plate is secured to the collar near the second side edge, whereby the collar and the first end Compression casing assembly, characterized in that the plate and the second end plate form a gas tight pressure vessel.

4. The feature of item 3 above, wherein the volume encapsulated by the first end plate in combination with the first edge region of the collar forms a first gas side manifold, has a first gas opening, and has a second edge of the collar. And the second end plate in combination with the zone defines a second gas side manifold and has a second gas opening for at least one cell stack.

5. The feature of item 3 above, wherein the first end plate has a first gas opening, forms a first gas side manifold, the second end plate has a second gas opening, and at least one cell stack. Forming a second gas side manifold for the compression casing assembly.

6. Compression casing according to any of the preceding features, wherein the collar is made of a thin metal sheet, preferably ferritic or austenitic stainless steel or nickel alloy, preferably inconel. Assembly.

7. The end plate of any of the preceding features 1-6, wherein the end plate is welded, threaded, clamped, riveted, beaded, glued or flanged. Compression casing assembly, characterized in that fixed to the collar by.

8. The compression casing assembly of any of the preceding features, wherein two or more of the cell stacks are disposed side by side and / or in a matrix pattern with the bottom side facing up.

9. The compression casing assembly of any of the preceding features, wherein two or more of the assemblies are connected in series by connecting the second side edge of the preceding assembly to the first side edge of the subsequent assembly.

10. Compression casing assembly according to feature 9 above, wherein openings for the introduction of purge gas, fuel and / or refrigerant are provided in the connected edge zone in the middle of the series connected assemblies.

11. The method of any of features 1-10, wherein the at least one force distribution member is thermally insulated and is made of ceramic, glass, metal or a combination thereof, preferably porous calcium silicate or glass fiber reinforced calcium silicate. Compression casing assembly, characterized in that.

12. Compression casing assembly according to any of the preceding features, wherein the at least one flexible compressive force mat is made of a vibration damping material.

13. The method according to any of the preceding features, wherein the at least one flexible compressive force mat material is a refractory ceramic fiber or glass fiber, preferably magnesia-silica fiber, alumina fiber containing some silica, zirconia which is an oxide, A compression casing assembly comprising a low alkali aluminosilicate composition or vermiculite containing at least one of chromia or titania.

14. The assembly of any of features 1-13, wherein the assembly has a force distribution member applied to the top, bottom and two sides of the stack, and basically has a circular cross section, or the assembly is mounted on the top and bottom of the stack. A compression casing assembly having an applied force distribution member and essentially having an oval, elliptic or racetrack cross section.

15. A method of making at least one assembly according to any of features 1-14, wherein the method comprises

Providing at least one cell stack comprising a plurality of fuel cells or electrolytic cells

Providing at least one rigid force distribution member and at least one flexible compressive force mat

Surrounding the stack, the force distribution member and the compressive force mat with a rigid collar fixed on at least the top, bottom and two sides of the stack

Compressing the compressive force mat by tightening the collar, thereby applying a compressive force to the stack

Securing the collar in a taut state

Method comprising a.

16. The method according to the above feature 15,

Providing a first and a second end plate

Securing the first end plate to the collar near the first side edge of the collar and securing the second end plate to the collar near the second side edge of the collar

Method further comprising a.

17. The method according to the above feature 15,

Providing at least two said assemblies

Connecting the assemblies in series by fixing the second side edge of the preceding assembly to the first side edge of the subsequent assembly.

Method further comprising a.

18. Use of the compression casing assembly according to any of features 1-14 for vibration damping and protection of at least one fuel cell stack or electrolytic cell stack.

The invention is further illustrated by the accompanying drawings which illustrate examples of embodiments of the invention.
1 is an end cross-sectional view of a compression casing assembly including a battery stack encased in a case according to an embodiment of the invention.
2 is a side cross-sectional view of a compression casing assembly including a battery stack encased in a case according to an embodiment of the invention.
3 is an end cross-sectional view of a compression casing assembly including a battery stack encased in a case according to another embodiment of the invention.
4 is an isometric view of a compression casing assembly having an end plate that is a gas manifold, a radially extending fuel gas pipe and an axially extending oxidizing gas pipe.
5 is an isometric view of a compression casing assembly with an end plate that is a gas manifold, a radially extending fuel gas pipe and a radially extending oxidizing gas pipe.
6 is an isometric view of a compression casing assembly having an end plate that is a gas manifold, an axially extended fuel gas pipe, and an axially extended oxidizing gas pipe.
7 is a side sectional view of a compression casing assembly in which two stacks are connected in series cathode flow by edge-edge connection of two fixed collars.
8 is an end cross-sectional view of a compression casing assembly in which four stacks are connected in parallel cathode flow.
Part Number:
101, 201, 301, 401, 501, 601, 701, 801: Fixed rigid collar
102, 202, 302, 702, 802: upper rigid force distribution member
103, 203, 303, 703, 803: lower rigid force distribution member
104, 804: first side rigid force distribution member
105, 805: Second side rigid force distribution member
106, 206, 306, 706, 806: Flexible Compression Force Mat
109, 209, 309, 709, 809: battery stack, box
210, 410, 510, 610, 710: oxidizing gas inlet manifold
211, 411, 511, 611, 711: oxidizing gas inlet pipe
212, 712, 812: oxidizing gas outlet manifold
213, 413, 513, 613, 713: oxidizing gas outlet pipe
421, 521, 621: fuel gas inlet pipe
422, 522, 622: fuel gas outlet pipe
731: intermediate oxidizing gas manifold

With reference to FIG. 1, in one embodiment, the cell stack 109 to be compressed is box-shaped and is a cell stack in which the internal and external manifolds are combined. Fuel gas is supplied to and removed from the cell through an internal manifold connected to a fuel pipe (not shown). The oxidizing gas is fed to one edge of the cell (the fuel cell or electrolytic cell described above), flows over the cell area, and then removed from the other edge of the cell. When the cell is stacked, these parallel edges form two sides of the stack, which must be connected to two external manifolds. In FIG. 1, the box battery stack 109 is seen from the oxidizing gas inlet side. In this embodiment, rigid and thermally insulated force distribution members 102, 103, 104, 105 are applied to the top and bottom sides in addition to the four sides of the cell stack, ie two sides without openings for oxidizing gas.

As can be seen in FIG. 1, the four force distribution members each have a planar surface in contact with the cell stack, but the opposite surface of each force distribution member has a convex shape in one dimension and linear in a dimension parallel to the axis of the convex curve. Has a shape. In this embodiment, the convex curve of the force distribution member has a circular arc shape, more specifically an arc shape making up 4/1 of a circle. Thus, when the four force distribution members are each disposed on their corresponding faces in the stack, the four convexly shaped surfaces together form a cylindrical shape, with virtually no gap between the force distribution member and the stack. . The force distribution member can be made of a wide range of materials depending on the specific requirements of the application (heat insulation, gas impermeability, stiffness, additional functions). Examples of materials for the force distribution member are ceramic, glass, metal or combinations thereof, porous calcium silicate or glass fiber reinforced calcium silicate. In some applications thermal insulation is a desirable property of the force distribution member, but in other applications thermal insulation is not necessarily required. The force distribution member may even be an active component such as an anode heat exchanger.

The flexible compression mat is disposed around the assembly of the cell stack and the four force distribution members. The flexible compression mat tightly surrounds the assembly, and the mat ends are firmly engaged with each other, for example, by being assembled in a butt end fixation or tongue and groove manner. Compression mats are characterized by being very well suited for the compression of SOFCs under high temperature conditions. It is substantially airtight, heat resistant and can be compressed in such a way that the longer it is compressed, the greater the compressive force exerted on the direction of compression. Since the compression mat exerts a compressive force on the cell stack when the proper distance is compressed, no metallic compression springs are required. This "suitable distance" can be determined by the known elastic modulus of the compression mat, or simply by repeated experiments. The prerequisite is the stack requirement for compression, which is determined experimentally and is specific to the type of cell stack in question. The stack compressive force is obtained by tensioning the compression mat around the stack with the required force. Another method of determining the suitable compression distance of the compression mat is to install a force measuring device between the stack box surface and the force distribution member, and then compress the surrounding compression mat until the desired compression force is achieved in the stack, according to the force measuring device. . Once this experiment has been performed, additional compression assemblies can be produced using a similarly characterized compression mat based on this data. The necessary characteristics for the compression mat can be obtained using a group of materials known to those skilled in the art, some of which are refractory ceramic fibers or glass fibers, magnesia-silica fibers, alumina fibers containing some silica, zirconia which is an oxide, Low alkali aluminosilicate compositions or vermiculite containing one or more of chromia or titania.

The compression casing assembly is completed with a fixed rigid collar surrounding the stack, the force distribution member and the compression mat. A fixed collar serves several purposes, most importantly securing the compression mat to the desired compression required to provide the stack with the required compression force. The fixed collar can be made of a group of materials such as metals, plastics, composite materials, glass fibers, carbon fibers or other suitable materials known to those skilled in the art. For example, if the fixed collar is made of steel, it can be applied around the assembly as a thin sheet, to be tensioned by the desired clamping force by a hose clamp or the like. When the desired dimensions are reached, the sheet can be welded along the edges, thereby forming a tightly fixed cylindrical collar surrounding the compression mat, the force distribution member and the stack. Fixed collars are also used for protection of the cell stack. When the stack is put into the can as described, it is protected against heat, protected against shock and vibration by a flexible compression mat, and well protected against crushing, scratches, etc. by the collar.

The collar may also serve as part of the oxidizing gas inlet and outlet manifold. When mounted with narrow tolerances, the cell stack, force distribution member, compression mat and fixed collar form a substantially airtight barrier between the oxidant gas inlet side of the stack and the oxidant gas outlet side of the stack. Even if a small amount of oxidizing gas is allowed to pass through the compression assembly from the inlet side to the outlet side, this will only have an adverse effect on cell stack performance.

2, where the dimensions of the fixed collar are larger and wider than the fuel cell stack 206 (or electrolytic cell stack) and the force distribution members 202 and 203 and the compression mat 206 around it, It can be seen that the assembly has an enclosing rim on both the oxidizing gas inlet side and the oxidizing gas outlet side. When the rim is provided with a cap, very simple inlet manifold 210 and outlet manifold 212 are achieved. The cap can be made of the same steel material as the fixed collar, and the two can be welded together, thereby providing a tight and very rigid manifold as compared to an external manifold, a known technique that must be fixed by individual seals and mounting systems. Is provided. As such, the compression casing assembly is formed as a pressure vessel that can be easily fabricated to dimensions that can withstand substantial excess pressure, such as, for example, found in turbine systems. Operating the fuel cell stack by such boosting also increases the Nernst potential, which also significantly increases the electrical efficiency of the fuel cell stack. The oxidizing gas is provided to the inlet manifold via the oxidizing gas inlet pipe 211 and exits from the outlet manifold via the oxidizing gas outlet pipe 213. Fuel gas is provided to and exited from the stack through internal manifolds (not shown) and fuel inlet and outlet pipes (not shown) known in the art, and with fixed collars, compression mats and even force distribution members (not shown). Through the opening to the internal manifold of the stack. The fuel gas pipe can be sealed to a collar, compression mat and force distribution member fixed by known techniques and materials such as welding, soldering and the like.

In a further embodiment, not shown, the compression casing assembly comprising one or more stacks may be rigid and may have side manifolds even when the collar is no wider than the stack, force distribution member and compression mat assembly. If the collar is substantially the same as the rest of the assembly, the end plate can also be easily mounted to the collar by any suitable technique. The end plate is slightly convex in shape and the manifold volume will be formed to distribute the oxidizing gas between the cells, and if the metal is used, the end plate may simply be welded to the collar, similar to the solution according to FIG. Rivets may be used, soldered or beaded, thereby forming an airtight, pressure resistant and very rigid assembly.

The compression casing assembly according to FIG. 2 forms such a simple, hermetic, stable and rigid cell stack unit.

It may be advantageous to connect the stacks in series to increase fuel cell efficiency. As shown in FIG. 7, the assembly of the present invention is well suited for this purpose, where the outlet manifold 712 of the main stack 709 and the inlet manifold 710 following the stack 709 can be omitted, thereby. This is because the two stationary collars are simply welded together.

In this way, when the surrounding fixed collar 701 is wider than the stack, a volumetric intermediate manifold 31 occurs between the two stacks connected in series. Pipes can be connected to the intermediate manifold, which allows injection of supplemental oxidizing gas, steam, water fog or other process gases or fluids. Again, the compression casing assembly of the present invention provides a simple and robust unit capable of simple, robust, pressure resistant and hermetic series connection of multiple fuel cell stacks.

As shown in FIG. 8, parallel connection of a fuel cell stack or an electrolytic cell stack can also be achieved according to the invention. Two or more stacks 809 may be disposed above or side by side. Although many stacks are placed in parallel, force distribution members 802, 803, 804, 805 can be mounted around the stack, and compression mats 806 can be placed between the stacks to fill gaps and even out irregularities. . In this way a simple, robust, pressure resistant and hermetic compression casing assembly can be achieved even when two or more stacks are arranged in parallel.

With reference to FIG. 3, an embodiment is shown in which force distribution members 302 and 303 are applied only above and below cell stack 309. Only a compression mat 306 is applied to the side of the stack, which is not intended to compress, but merely to achieve the hermetic enclosure of the stack. This embodiment takes advantage of the fact that the cell stack mainly requires compression of the top to the bottom, and lateral compression is less important for the durability and efficacy of the stack. Thus, in this embodiment, not only the side force distribution member but also a considerable amount of space is saved.

4, 5 and 6 illustrate how fuel inlets 421, 521, 621 and outlet pipes 422, 522, 622 can be connected to a fuel cell stack or an electrolytic cell stack in a can. The pipes extend over the internal manifold of the cell stack through the collars 401, 501, 601 and further through the compressive force mat and force bonsai member (not visible in FIGS. 4, 5, and 6). In some embodiments, the pipe may be made of any material, for example steel, which may be welded or soldered to the collar, resulting in a rigid and airtight battery assembly. 4 is similar to the embodiment according to FIGS. 1 and 2, a different solution is shown in FIG. 5, in which oxidizing gas pipes 511, 513 are also mounted on the collar cylinder side, which are substantially orthogonal to the cylinder central axis. Is extended. This embodiment may be advantageous in applications where it is desirable to have tubing only on one side of the battery assembly. In FIG. 6 an embodiment is shown in which the oxidizing gas 611, 613 and fuel gas 621, 622 pipes both extend substantially parallel to the cylindrical axis through the oxidizing gas manifold.

Claims (18)

A compression casing assembly for at least one cell stack consisting of a plurality of fuel cells or electrolytic cells, the at least one cell stack
Top
-Bottom side
-Multiple aspects
Fuel gas inlet and outlet adapted to communicate with fuel gas inlet and outlet manifolds;
Oxidant gas inlet and outlet adapted to communicate with oxidant gas inlet and outlet manifolds;
Including,
The compression casing assembly comprises at least one rigid force distribution member, at least one flexible compressive force mat and at least one fixed rigid collar comprising an inner surface, an outer surface and first and second side edges,
At least one force distribution member
An upper portion having a first planar surface facing the top of the cell stack and a second convexly shaped second surface opposite the first planar surface facing in the direction towards the inner surface of the fixed collar;
A lower portion having a first planar surface facing the bottom of the cell stack and a second surface of essentially convex shape opposite the first planar surface facing in the direction towards the inner surface of the fixed collar;
Including;
The fixed rigid collar surrounds at least one cell stack, at least one force distribution member and at least one flexible compressive force mat at least on the top, the bottom and two of the sides,
The fixed rigid collar is pre-tensioned so that a compressive force perpendicular to the surrounding fixed rigid collar is essentially perpendicular to the top, the bottom and the two sides by at least one flexible compressive force mat and at least one force distribution member. Is delivered to at least one cell stack in the
Thus, a compression is characterized in that the basically convexly shaped second surface of the upper and lower portions of the at least one force distribution member provides a uniformly distributed surface pressure on at least the top and bottom surfaces of the at least one cell stack. Casing assembly. The rigid rigid collar of claim 1, wherein the at least one force distribution member and the at least one compressive force mat comprise the top, bottom and two sides of the at least one cell stack and the surrounding rigid rigid collar at least in a portion of an axial range of the collar. And a substantially hermetic seal between the inner surfaces of the compression casing assembly. 3. The device of claim 2, wherein a first end plate is secured to the collar near the first side edges, and a second end plate is secured to the collar near the second side edges, thereby providing a collar and a first end plate. And the second end plate forms an airtight pressure vessel. 4. The volume of claim 3, wherein the volume, combined with the first edge region of the collar, encapsulated by the first end plate forms a first gas side manifold, has a first gas opening, and The second end plate in combination forms a second gas side manifold and has a second gas opening for at least one cell stack. 4. The method of claim 3, wherein the first end plate has a first gas opening, defines a first gas side manifold, and the second end plate has a second gas opening, and is configured for at least one cell stack. And a second gas side manifold. Compression casing assembly according to claim 1, wherein the collar is made of a thin metal sheet, preferably ferritic or austenitic stainless steel or nickel alloy, preferably inconel. . 7. Compression casing assembly according to any one of the preceding claims, wherein the end plate is fixed to the collar by welding, threaded connection, clamp connection, rivet, beading, glue or flange connection. 8. Compression casing assembly according to any of the preceding claims, characterized in that at least two of said cell stacks are arranged side by side and / or in a matrix pattern with the bottom side facing upwards. 9. The compression casing assembly of claim 1, wherein at least two of the assemblies are connected in series by connecting the second side edge of the preceding assembly to the first side edge of the subsequent assembly. 10. 10. Compression casing assembly according to claim 9, wherein openings for the introduction of purge gas, fuel and / or refrigerant are provided in the connected edge zone in the middle of the series connected assemblies. The at least one force distribution member is thermally insulated and is made of ceramic, glass, metal or a combination thereof, preferably porous calcium silicate or glass fiber reinforced calcium silicate. Compression casing assembly, characterized in that the manufacturing. 12. Compression casing assembly according to any preceding claim, wherein the at least one flexible compressive force mat is made of a vibration damping material. 13. The at least one flexible compressive force mat material is an alumina fiber, oxide containing some degree of refractory ceramic fiber or glass fiber, preferably magnesia-silica fiber, silica. A compression casing assembly comprising a low alkali aluminosilicate composition or vermiculite containing at least one of zirconia, chromia or titania. 14. The assembly of any of claims 1 to 13, wherein the assembly has a force distribution member applied to the top, bottom and two sides of the stack, and basically has a circular cross section, or the assembly has a top surface of the stack. A compression casing assembly having a force distribution member applied to the underside and having an essentially oval, elliptical or racetrack cross section. A method of making at least one assembly according to any one of claims 1 to 14, wherein the method comprises
Providing at least one cell stack comprising a plurality of fuel cells or electrolytic cells
Providing at least one rigid force distribution member and at least one flexible compressive force mat
Surrounding the stack, the force distribution member and the compressive force mat with a rigid collar fixed on at least the top, bottom and two sides of the stack
Compressing the compressive force mat by tightening the collar, thereby applying a compressive force to the stack
Securing the collar in a taut state
Method comprising a. The method of claim 15,
Providing a first and a second end plate
Securing the first end plate to the collar near the first side edge of the collar and securing the second end plate to the collar near the second side edge of the collar
≪ / RTI > The method of claim 15,
Providing at least two said assemblies
Connecting the assemblies in series by fixing the second side edge of the preceding assembly to the first side edge of the subsequent assembly.
≪ / RTI > Use of a compression casing assembly according to any one of claims 1 to 14 for vibration damping and protection of at least one fuel cell stack or electrolytic cell stack.

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